Multi-well test plates are well known in scientific areas, such as biotechnology, for allowing the detection and measurement of substances present in translucent liquid samples. Generally, this is accomplished by measuring the light absorbence characteristics of the sample through one or more spectroscopy procedures. Typically, a framework of test wells is open at the top for receiving the liquid samples and is closed with a transparent bottom, formed of a polymer or glass, for allowing light radiation penetration in a wavelength region necessary for a particular study. These studies, commonly referred to assays, may include drug concentration assays, drug metabolite assays, enzyme activity assays, enzyme cofactor assays, fluorescent probe excitations or emissions, DNA spectral shifts or DNA and protein concentration measurements, as well as many other studies.
Due to the advantageous physical and optical properties of glass, glass bottom test plates can be more desirable than test plates having bottoms formed from a transparent polymer, such as polyolefins, fluorpolymers, polyesters, or other homopolymers and copolymers. The thickness of the transparent bottom has also been recognized as an important factor for achieving accurate test results. Moreover, when applying a glass sheet or panel to the bottom of a polymeric framework, for example, it has been difficult to achieve a seal in surrounding relation to each test well. Manufacturing methods involving an adhesive securement of the glass panel to the test well framework can be very slow and result in inadequate adhesion, inadequate sealing around the bottom of each well, adhesive migration into the test wells or other problems.
The present invention is therefore generally directed to the manufacture of multi-well test plates having an upper frame structure with multiple test wells and a thin, glass or other transparent bottom panel adhered to the framework in a fast and effective manner which does not have any adverse consequences related to the subsequent use of the test plate.